Adding mass is easy. That is what depleted uranium is all about and it used to be used for the purpose of balancing aircraft regularly. Not sure if it still is but during the 80s it was a pretty common practice. Of course the missing mass could be used for something mission related like armor or such. The issues with engines further out can be dealt with by moving the electric motors or assuming that the Project has better electric motors.

Quote:

Originally Posted by mmartin798

This is where things can get a little off. There is an electric motor that can be stacked to provide 300 kW continuous to the rotor in place of the C20R. It would have a length of 540 mm, diameter of about 245 mm and a total mass of 129 kg. Add in the (3rd edition) manportable 20MW reactor at 15kg and you have 145 kg give or take fully fueled. The non-fusion MD500/520 carries 183kg of fuel in addition to the 78.5 kg of the engine for about 260 kg. The two fuel cells of the MD500 are under the floor more or less centered around the rotor. Assuming the reactor can fit inside the space as the fuel cells, we will still have to add more weights to the front of the MD500 for load and balance.

This is doable in the MD500 case, but the electric motors will tend to be heavier and smaller than the ones they replace and the reactor, assuming 20MW sufficient, will be lighter than the fuel. This will be a problem with planes with engines mounted far out on the wings. This will increase the moment of inertia and will impact handling.

So the takeaway is that center line drive trains should be easy to convert with little impact to the flight characteristics. Anything with the engine further out on the wing and you will have some slower turn and roll.

Adding mass is easy. That is what depleted uranium is all about and it used to be used for the purpose of balancing aircraft regularly. Not sure if it still is but during the 80s it was a pretty common practice. Of course the missing mass could be used for something mission related like armor or such. The issues with engines further out can be dealt with by moving the electric motors or assuming that the Project has better electric motors.

Quote:

Originally Posted by mmartin798

This is where things can get a little off. There is an electric motor that can be stacked to provide 300 kW continuous to the rotor in place of the C20R. It would have a length of 540 mm, diameter of about 245 mm and a total mass of 129 kg. Add in the (3rd edition) manportable 20MW reactor at 15kg and you have 145 kg give or take fully fueled. The non-fusion MD500/520 carries 183kg of fuel in addition to the 78.5 kg of the engine for about 260 kg. The two fuel cells of the MD500 are under the floor more or less centered around the rotor. Assuming the reactor can fit inside the space as the fuel cells, we will still have to add more weights to the front of the MD500 for load and balance.

This is doable in the MD500 case, but the electric motors will tend to be heavier and smaller than the ones they replace and the reactor, assuming 20MW sufficient, will be lighter than the fuel. This will be a problem with planes with engines mounted far out on the wings. This will increase the moment of inertia and will impact handling.

So the takeaway is that center line drive trains should be easy to convert with little impact to the flight characteristics. Anything with the engine further out on the wing and you will have some slower turn and roll.